Lane count estimation

ABSTRACT

A method for assigning a number of lanes and a direction of travel on a path includes receiving location data including a plurality of location points, projecting the plurality of location points on to an aggregation axis perpendicular to a centerline of the vehicle path, grouping the plurality of location points as projected onto the aggregation axis into one or more clusters, and determining the number of vehicle lanes of the vehicle path based on a count of the one or more clusters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/238,384 entitled “LANE COUNT ESTIMATION,” filed on Jan. 2, 2019, theentire disclosure of which is hereby incorporated by reference.

FIELD

The following disclosure relates to a system for estimating a number oflanes on a road or vehicle path.

BACKGROUND

A map or navigation database may contain attributes about roads orvehicle paths, including a number of lanes of vehicle traffic. Thenumber of lanes may be used to generate a navigation command. Thenavigation command or the number of lanes may be sent to a user (e.g. toa user's mobile device) or to a vehicle.

The number of lanes for the road or vehicle path may be determined basedon top-down images of the road or path. For example, satellite imageryof roads and paths may be manually reviewed to count the number of lanespresent. Additionally or alternatively, images taken from street levelmay be reviewed to count the number of lanes. Manual counting of vehiclelanes may be time consuming and limited by the resolution of thereviewed images. In some cases, machine learning may be applied to theimages to count the lanes.

SUMMARY

In one embodiment, a method for assigning a number of vehicle lanes on avehicle path is disclosed. The method includes receiving location dataincluding a plurality of location points, projecting the plurality oflocation points on to an aggregation axis perpendicular to a centerlineof the vehicle path, grouping the plurality of location points asprojected onto the aggregation axis into one or more clusters, anddetermining the number of vehicle lanes of the vehicle path based on acount of the one or more clusters.

In another embodiment, an apparatus for assigning a number of vehiclelanes on a vehicle path is disclosed. The apparatus includes a receiverconfigured to receive location data including a plurality of locationpoints, an aggregator configured to project the plurality of locationpoints on to an aggregation axis perpendicular to a centerline of thevehicle path and group the plurality of location points as projectedonto the aggregation axis into one or more clusters, and a geographicdata processor configured to determine the number of vehicle lanes ofthe vehicle path based on a count of the one or more clusters.

In another embodiment, a non-transitory computer-readable medium isdisclosed that includes instructions that when executed are operable toreceive location data including a plurality of location points from oneor more mobile devices, vehicles, or mobile devices and vehiclestraversing a path, the plurality of location points including adirection of travel of the one or more mobile devices, vehicles, ormobile devices and vehicles, project the plurality of location points onto an aggregation axis perpendicular to a geometric reference line ofthe path, group a subset of the plurality of location points having asame or similar direction of travel as projected onto the aggregationaxis into one or more clusters, and determine a number of traffic lanesand a direction of the path based on a count of the one or more clustersand the direction of the subset of the plurality of location points.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention are described herein withreference to the following drawings.

FIG. 1 illustrates an example system for collecting location data.

FIG. 2A illustrates an example vehicle path with location data.

FIG. 2B illustrates an example projection of location data.

FIG. 3 illustrates an example clustering of projected location data.

FIG. 4A illustrates an example curved path.

FIG. 4B illustrates an example set of linear segments approximating acurved path.

FIG. 4C illustrates an example projection of location data for one ormore linear segments.

FIG. 5 illustrates an example flowchart for estimating a number oflanes.

FIG. 6 illustrates another example system for collecting location data.

FIG. 7 illustrates a further example system for collecting locationdata.

FIG. 8 illustrates an example server.

FIG. 9 illustrates an example system for assigning a number of lanes ona path.

FIGS. 10 and 11 illustrate example geographic databases.

DETAILED DESCRIPTION

The number of lanes present on a road or vehicle path may be determinedfrom location data. For example, location data from vehicles or usestraversing the road or vehicle path may be used to determine the numberof lanes. The location data may be a measurement of a position. Forexample, a global positioning system (GPS) or global navigationsatellite system (GNSS) may be used to measure a location of a user orvehicle traversing the road or path.

Vehicles traversing a road or path may remain in a lane, resulting ingaps between vehicles in different lanes. Accordingly, location datarecorded by the vehicle or a user traversing the path may be confined toone lane of the road or path. Where location data from multiple vehiclesis collected, the location data may be denser (e.g. more location dataper linear or two-dimensional space) within a lane than between lanes. Adifference in density may be more pronounced where vehicles maintain“lane discipline” and remain in a lane.

The location data may be collected from multiple vehicles or userstraversing a path. The location data may include a coordinate orregistration of the vehicle or user. For example, the location data mayinclude a latitude, a longitude, a height, or other information.Additionally or alternatively, the location data may include aregistration relative to the road or path. For example, the locationdata may include a length along a path, a lateral distance from acenterline of the path, and a height above the path. In some cases, theregistration may be determined by matching the location data to a map.

The location data, including the coordinates or registration, may begrouped into one or more clusters. The number of clusters of thelocation data may be a count of the number of lanes on the road or path.In some cases, a density-based clustering method may be applied to thelocation data. For example, the density-based spatial clustering ofapplications with noise (DBSCAN) clustering method may be used.

While the clustering method may be expected to create clusterscorresponding to the number of lanes, error in the measurement of thevehicle or user location reduces the difference in density between thelane and the space between lanes on the road or path. Though a vehiclemay be traveling in a single lane for the length of the road or path,errors in measurement of the location of the vehicle may indicate thevehicle was traveling in between lanes or in multiple lanes. Inparticular, errors in the lateral position of the vehicle or userrelative to the path may obscure any difference in location data densitybetween lanes. In some cases, location measurements from GPS systems mayhave errors between 1 and 20 meters. Errors may be caused by weaksignals received from positioning satellites (e.g. due to trees,tunnels, or tall buildings attenuating or reflecting positioningsignals).

Applying a clustering method to the location data including the errormay result in clusters that do not correspond to lanes on the road orpath. For example, a clustering method may group a location point of thelocation data into one cluster based on a distance between the locationpoint and neighboring location points of the location data. Due tolocation data errors and a lack of definition between lanes (e.g.similar location data density across the road or path), the clusteringmethod may group the location data into clusters that are perpendicularto the road or path.

Pre-processing the location data before clustering may improve thecorrespondence between a number of clusters and a number of lanes on aroad or path. For example, projecting the location data points onto aline that is perpendicular to a center line of the road or path andeliminating outlier location data may make it more likely that aclustering method applied to the processed location data results in anumber of clusters that accurately counts a number of lanes on the roador path. For curved roads or paths, the path may be approximated by oneor more linear segments, each location point of the location data may bematched to one of the segments, and the location data may be projectedonto lines perpendicular to each linear segment. The number of clusters(and number of lanes) for each segment may be collected and the numberof lanes for the whole curved path may be determined as the most commonnumber of lanes for the segments.

FIG. 1 illustrates an example system for collecting location data. Oneor more vehicles 124 are connected to a server 125 though a network 127.The vehicles 124 may be directly connected to the server 125 or throughan associated mobile device 122 or another intermediary. The mobiledevices 122 and vehicles 124 may include a position sensor 101configured to measure a position of the mobile device 122 or vehicle124. The server 125 may be connected to a database 123. Additional,different, or fewer components may be included.

The mobile device 122 may be a standalone mobile device, such as asmartphone, or a device integrated with a vehicle 124. The mobile device122 may include or be in communication with a positioning sensor 101.The mobile device may be configured to store location informationgenerated by the positioning sensor 101. In some cases, the mobiledevice may send the location information to the server 125. The mobiledevice may include an application, such as a mapping or navigationapplication. In some cases, the application may receive the locationinformation. The mobile device 122 may receive mapping or navigationinformation from the server 125. The application may use the receivedmapping or navigation information. For example, the application may usea navigation command sent by the server and received by the mobiledevice 122 to display navigation information on the mobile device 122.

The vehicle 124 may be any kind of machine that transports good orpeople. For example, the vehicle may be a motor vehicle (e.g. a car or atruck,) an aircraft (e.g. an airplane, helicopter, or a drone), awatercraft (e.g. a boat or hovercraft), or another kind of vehicle. Thevehicle 124 may contain or be in communication with a positioning sensor101. The vehicle 124 may be configured to send location informationgenerated by the positioning sensor to the server 125 or to the mobiledevice 122. In some cases, the mobile device 122 may receive thelocation information from the vehicle 124 and send the locationinformation to the server 125.

The vehicles 124 and mobile devices 122 may communicate with the server125 through the network 107. The network may be one of a variety oftypes of wireless networks. Example wireless networks include cellularnetworks, the family of protocols known as Wi-Fi or IEEE 802.11, thefamily of protocols known as Bluetooth, or another protocol. Thecellular technologies may be analog advanced mobile phone system (AMPS),the global system for mobile communication (GSM), third generationpartnership project (3GPP), code division multiple access (CDMA),personal handy-phone system (PHS), and 4G or long-term evolution (LTE)standards, 5G, DSRC (dedicated short-range communication), or anotherprotocol.

The database 123 may be a geographic database. The geographic databasemay store information including maps and location data generated by theposition sensors 101. The geographic database may be configured to sendinformation such as map information to the server 125. Informationstored in the database 123 may be updated by the server 125.

The server 125 may be configured to receive location data or locationinformation generated by position sensors 101 from the mobile devices122 and the vehicle 124 through the network 107. The server 125 may beconfigured to process the location information to update a map or togenerate a mapping or navigation command. For example, the server 125may be configured to determine a number of lanes of path based on thereceived location information and to update a map stored in the database123 based on the number of lanes. In another example, the server isconfigured to determine a navigation command for the mobile device 122or the vehicle 124 based on the received location information. Thenavigation command may be an autonomous driving command instructing themobile device 122 or the vehicle 124 to take an action. The navigationcommand may include a route for the mobile device 122 or vehicle 124.

The position sensor 101 may generate location data including one or moremeasurements of the position sensor at a point in time. The locationdata may be generated by receiving GNSS or GPS signals and comparing theGNSS or GPS signals to a clock to determine the absolute or relativeposition of the vehicle 124 and/or mobile device 122. The location datamay be generated by receiving radio signals or wireless signals (e.g.,cellular signals, the family of protocols known as Wi-Fi or IEEE 802.11,the family of protocols known as Bluetooth, or another protocol) andcomparing the signals to a pre-stored pattern of signals (e.g., a radiomap). The mobile device 122 may act as the position sensor 101 fordetermining the position, or the mobile device 122 and the positionsensor 101 may be separate devices. Additionally or alternatively, thevehicle 124 may act as the position sensor 101 for determining theposition, or the vehicle 124 and the position sensor 101 may be separatedevices.

The location data may describe a geographic location, for example with alongitude value and a latitude value. In addition, the location data mayinclude a height or altitude. Additionally or alternatively, thelocation data may include a heading. The location data may be collectedover time and include timestamps. In some examples, the location data iscollected at a predetermined time interval (e.g., every second, every100 milliseconds, or another interval). In some examples, the locationdata is collected in response to movement by the position sensor 101(e.g., the sensor reports location information when the position sensor101 moves a threshold distance). The predetermined time interval forgenerating the location data may be specified by an application or bythe user. The interval for providing the location data from the mobiledevice 122 to the server 125 may be may the same or different than theinterval for collecting the location data. The interval may be specifiedby an application or by the user.

The mobile device 122 may transmit the location data to the server 125so that the server 125 may provide a service to the mobile deviceaccording to the location data. For example, the mobile device 122 orvehicle 124 may send location data to the server 125 and the server 125may return a location-based service to the mobile device 122 or vehicle124, such as a navigation command. In some cases, the navigation commandmay include a route, a position of the mobile device 122 or vehicle 124on a map, or an autonomous driving command.

FIG. 2A illustrates an example path 201 with location data 203. Thelocation data may be projected along a projection vector 205 to anaggregation axis 207 that is perpendicular to a centerline 209 of thepath 201. The centerline 209 may be centered between the path boundaries211.

The path 201 may be a road or other path traversed by a vehicle or user.For example, the path 201 may be a path suitable for a pedestrian, adrone, a boat, a bike, a vehicle, or a handicapped user. The path 201may be divided into one or more lane to guide traffic along the path201. Vehicle or user traffic may flow in one or both directions alongthe path 201. For example, the path 201 may be a two-lane roadaccommodating one lane of vehicle traffic in either direction along thepath 201. In another example, the path may be a multi-lane highwayaccommodating multiple lanes of traffic in either direction. Though thepath 201 shown includes three lanes, any number of lanes may be presenton the path 201. The number of lanes on the path 201 may be not be knownor no number of lanes may be associated with the path 201.

The location data 203 may be a measurement of a position of a user or avehicle traversing the path 201. In some cases, a positioning sensor ofthe vehicle or of a user device may measure the position or location ofthe user or vehicle traversing the path 201. The location data 203 mayinclude one or more location measurements from one or more users orvehicles traversing the path 201. For example, a vehicle may recordmultiple measurements of the location of the vehicle at different pointsduring traversal of the path. A positioning sensor may measure thelocation. For example, the positioning sensor may use GPS or GNSS tomeasure a location of the vehicle or the user. The positioning sensormay be a part of a vehicle or of a user device. The user device may be amobile device such as a cell phone.

The projection vector 205 may represent the path of a portion of thelocation data 203 as the data 203 is projected onto the aggregation axis207. Each measurement of the location data 203 may be projected along avector 205 onto the axis 207. The projection vector 205 may follow thecourse of the path 201. In some cases, the projection vector 205 may beparallel to a centerline 209 or boundary 211 of the path 201. In someother cases, the projection vector 205 may remain proportionally betweenthe boundaries of the path 201. For example, the vector 205 may remainat a distance of one quarter of the width of the path 201 away from oneof the boundaries as the path 201 narrows from one end to another. Instill other cases, the vector 205 may be perpendicular to theaggregation axis 207.

The aggregation axis 207 may be defined as perpendicular to a centerline209 of the path 201. The aggregation axis 207 may be a line on which thelocation data 203 is projected. By projecting the location data 203 ontothe aggregation axis 207, information about the position of the locationdata 203 along the length of the path 201 may be removed and informationabout the position of the location data 203 along a width of the path201 may be preserved. The information in the location data 203 along thelength of the path 201 may be removed because every point of thelocation data 203 shares the position of the aggregation axis along thelength of the path 201. The aggregation axis 207 may be defined at astart, end, or other position along the path 201 or a segment of thepath 201. Multiple aggregation axes 207 may be defined for a path 201.For example, where the path 201 has a curve, the path may be broken intosegments and an aggregation axis 207 defined for each segment of thepath 201.

The centerline 209 may be defined as being in the middle of the pathboundaries 211. For example, the centerline may divide in half a widthof the path 201. Additionally or alternatively, the location of thecenterline 209 may be predefined and the boundaries 211 defined relativeto the centerline 209. For example, the boundaries 211 may be located ata predefined distance from the centerline 209. In some cases, thecenterline 209 may be an estimate of the center of the path 201 or ageometric reference line for the path. For example, the centerline 209may occupy an estimated position that differs in position from ageometric center of the path 201. In another example, the centerline 209may be a geometric reference line corresponding to a course or positionof the path 201. The geometric reference line may generally indicate theposition of the path 201 but not precisely or perfectly indicate anexact boundary, position, center, or other geometric or geographicattribute of the path 201.

The path boundaries 211 may indicate an edge of the path 201. Forexample, the boundaries 211 may be located at the width of the path 201.Location data 203 outside of the boundaries 211 may be ignored orexcluded from determining a number of lanes of the path 201. In somecases, the positions of the path boundaries 211 may not be known. Forexample, only the centerline 209 of the path 201 is known but not thepath boundaries 211.

FIG. 2B illustrates an example projection of location data 203. Whenprojected onto the aggregation axis 207 perpendicular to the center line209, the location data 203 may become projected location data 213.

The projected location data 213 may lie along the aggregation axis 207.Outlier location data points of the location data 203 may be removedfrom the location data 203 prior to the location data 203 beingprojected on the aggregation axis 207 to form projected location data213. Removing outlier data points may improve the efficiency andaccuracy of clustering the projected location data 213.

FIG. 3 illustrates an example clustering of projected location data 313.The projected location data 313 may lie on an aggregation axis 307 thatis perpendicular to a centerline 309 of a path. The projected locationdata 313, aggregation axis 307 and centerline 309 may be the projectedlocation data 213, aggregation axis 207, and centerline 209 of FIG. 2.The projected location data 313 may be grouped into one or more clusters315.

The clusters 315 may be formed by applying a clustering method to theprojected location data 313. For example, a density-based clusteringmethod such as DBSCAN may be used. DBSCAN groups points of the locationdata into clusters by defining core points, reachable points, andoutliers. Alternatively, a hierarchical density clustering method suchas HDBSCAN may be used. For DBSCAN, a first location data point of theprojected location data 313 may be a core point if a minimum number ofother location points are within a predetermined distance (e.g. a“neighborhood”) of the core point. Every location data point in theneighborhood of the first point are directly reachable from the firstpoint. A second location data point may be a reachable point if a pathmay be constructed from the second point to the first point using onlyother points that are directly reachable from the first point (e.g. allthe location data points on the path are core points). A point may be anoutlier point if it is not reachable from any other points. A core pointmay form a cluster 315 with the other points that are reachable from(e.g. in the neighborhood of) the core point. By changing the value ofcluster criteria such as the distance of the neighborhood and theminimum number of other location points required to define a core point,different arrangements, and numbers of clusters 315 may be formed fromthe same projected location data 313. The different arrangements or setsof clusters created according to different cluster criteria may beevaluated by determining a degree of overlap between the clusters 315.Clusters with minimal overlap may more accurately reflect or correspondto the number of lanes on the path.

FIGS. 4A-4C illustrate fitting a curved path 401 with linear segments401 a-d. Aggregation axes 407 a-d may be defined for each segment 401a-d upon which location data 413 may be projected. The path 401 may bethe path 201 from FIG. 2 or path 301 from FIG. 3. The aggregation axes407 a-d may be the aggregation axis 207 from FIG. 2 or 307 from FIG. 3.The location data 413 may be the location data 203 or projected locationdata 213 from FIG. 2 or the projected location data 313 from FIG. 2.

The path 401 may have a bend or curved geometry. Because of the curve,it may be computationally expensive to project the location data 413onto an aggregation axis 407 of the path 401. Instead, the path 401 (andthe location data 413) may have segments 401 a-d fitted to it.

In some cases, the path 401 may be a straight line and have segments 401a-d fitted to it. For example, the path 401 may represent a straightsection of highway with an on ramp that merges into a lane. Because thepath 401 may have different widths and lanes along the length of thepath 401, it may be advantageous to break the straight path 401 intolinear segments 401 a-d and to determine the number of lanes presentover each section. For example, breaking a path into segments 401 a-dmay allow for each segment to be analyzed in parallel.

The segments 401 a-d may be fitted to the path 401. The segments 401 a-dmay be linear segments approximating a curvature of the path 401. Thesegments 401 a-d may be continuous over the length of the path 401. Thesegments 401 a-d may have a uniform length or different lengths. Acenterline of each respective segment 401 a-d. may represent thesegments 401 a-d.

The segments 401 a-d may be fitted to the curvature of the path 401using any technique. For example, one or more points on the segment 401a-d may be aligned on the path. A first end of the segment 401 a maycorrespond or have the same location as a first end of the path 401.Additionally or alternatively, a midpoint or other point on the segment401 a-d may lie on the path 401 and the segment 401 a-d may be orientedto be tangent to the path 401 at the point lying on the path 401.Combinations of the above techniques may be used to fit the segments 401a-d to the path 401. The segments 401 a-d may serve as a centerline forthe path 401.

The aggregation axes 407 a-d may be defined for each segment 401 a-d ofthe path 401. The aggregation axes 407 a-d may be determined to beperpendicular to the path segments 401 a. For example, the aggregationaxis 407 a may be perpendicular to the path segment 401

The location data 413 may be divided and associated with one of thesegments 401 a-d. For example, location data points of the location data413 lying on either side of the segment 401 a will be associated withsegment 401 a, but not any of the other segments. The location data 413associated with each segment 401 a-d may be grouped into clusters foreach segment. The number of clusters for each segment 401 a-d mayrepresent a number of lanes for that segment 401 a-d. The most popularnumber of lanes for the segments 401 a-d may be chosen as a number oflanes for the entire path 401. For example, segment 401 a may bedetermined to have two lanes while segments 401 b-d may be determined tohave three lanes. In this case, the path 401 may be determined to havethree lanes because the majority of segments 401 a-d were determined tohave three lanes. In another example, an average is taken of the numberof lanes determined for the segments 401 a-d.

FIG. 5 illustrates an example flowchart for estimating a number oflanes. Additional, different, or fewer acts may be provided. Forexample, acts S103 and S105 may not be performed. The acts may beperformed in any order. For example, acts S117-S121 may be performedafter acts S123 and S125. In some cases, acts S109 and S111 may bealternatives. In some other cases, both act S109 and act S111 areperformed. The acts of FIG. 5 may be performed by the server 125 incommunication with the geographic database 123.

In act S101, location data is received. The communication interface 805of the server 125 or the receiver 903 of the lane count estimator 901may receive the location data. The location data may indicate theposition of one or more vehicles or users traversing a path. Forexample, the location data may be collected by a position sensor of avehicle 124 or a mobile device 122 of the user. The location data mayinclude a plurality of location points. The location points may beindividual measurements of the location of a vehicle or a user. Apositioning sensor may measure the location. The positioning sensor maybe in communication with or a part of a vehicle or a mobile device of auser. In some cases, the location data includes only vehicles, users, ormobile devices moving in a similar direction. For example, the locationdata may only include positions of vehicles or users traversing the pathin the same or similar direction (e.g. east to west, north to south,left to right). Multiple sets of location data may be received for eachdirection of travel on the path. In some other cases, the location dataincludes position information from vehicles, mobile devices, and userstraveling in more than one direction. Subsets of the location data maybe formed that each contain vehicles, mobile devices, or users travelingin the same or a similar direction of travel along the path.

In act S103, one or more path segments are fitted to the path. Theserver 125 may be configured to receive the path from the database 123and fit the path segments to the path. Additionally or alternatively,the vehicle path processor 909 may be configured to fit the pathsegments to the path. The segments may be linear segments. Together, thepath segments may form a linear approximation of the path. The segmentsmay be continuous. In some cases, a geometry (e.g. a curvature) of thepath (or of a centerline of the path) may be defined based on one ormore shape points. The one or more path segments may be fit to the pathby connecting the shape points. In this way, the path segments mayfollow the geometry of the path or of a centerline of the path. Eachpath segment may have an aggregation axis.

In act S105, location data is matched to the path segments. The server125 may be configured to match the location data received by thecommunication interface 805 to the path segments via instructions storedin the memory 803 and executed by the processor 801. Additionally oralternatively, the vehicle path processor 909 may be configured to matchthe data to the segments. When the path is divided into segments orapproximated by path segments, the location data for the path may alsobe divided. Location points of the location data may be matched to apath segment. For example, a distance between the location point and theone or path segments may be determined. The location point may bematched to the nearest path segment. By matching the location points tothe segments, a subset of the location data may be associated with eachpath segment. The subset of location data may include only thosevehicles, users, or mobile devices traversing the path in the same or asimilar direction of travel.

In act S107, the location data may be projected onto an aggregationaxis. The server 125 may be configured to project the location datareceived by the communication interface 805 onto an aggregation axis viainstructions stored in the memory 803 and executed by the processor 801.Additionally or alternatively, the aggregator 911 may be configured toproject the data. The aggregation axis may be defined as perpendicularto a centerline of the path or path segment. The aggregation axis mayextend indefinitely or have a defined length. For example, theaggregation axis may extend to the width of the path. In some cases,location points outside the width or boundary of the path may beexcluded or removed from the location data. The location data may beprojected along a projection vector that is perpendicular to theaggregation axis. In some cases, projecting the location data mayinvolve moving a location data point to the aggregation axis. In someother cases, projecting the location data modifying the informationassociated with location points of the location data such that thelocation point is not registered long a length of the path and retainsonly information about a position of the location point along a width ofthe path. In still other cases, location data corresponding to only onedirection of travel may be projected onto the aggregation axis. Forexample, a subset of location data including vehicles, users, or mobiledevices traversing the path in the same or a similar direction of travelmay be projected onto the aggregation axis.

In act S109, a centroid of location data may be determined. The server125 may be configured to determine the centroid of the data received bythe communication interface 805 via instructions stored in the memory803 and executed by the processor 801. Additionally or alternatively,the statistics processor 907 may be configured to determine thecentroid. In some cases, the location data may contain multiplemeasurements of a vehicle or user traversing the path. These may beconsidered to be from the same “trace” of the vehicle or user. In somecases, the location points measuring the position of the same user orvehicle multiple times may be termed “vehicle-common” or “user-common.”The centroid of the vehicle-common or user-common location data may befound. The centroid may be a point at a geometric center of thevehicle-common or user-common location points.

In act S111, the vehicle-common or user-common location points may beprojected onto a line that is perpendicular to a centerline of a path orpath segment. The server 125 may be configured to project thevehicle-common or user-common location data via instructions stored inthe memory 803 and executed by the processor 801. Additionally oralternatively, the aggregator 911 may be configured to project thevehicle-common or user-common location data onto a line. In some cases,the vehicle-common or user-common location points may be projected ontothe line in a manner similar to act S107. A mean or average position ofthe vehicle-common or user-common location data as projected onto theline may be determined.

In act S113, a representative point of the vehicle-common or user-commonlocation data is chosen. The server 125 may be configured to choose therepresentative point via instructions stored in the memory 803 andexecuted by the processor 801. Additionally or alternatively, thelocation data processor 905 may be configured to determine therepresentative point. In some cases, the representative point is chosenbased on the centroid determined in act S109. For example, therepresentative point may be a location point of the vehicle-common oruser-common location data that is closest to the centroid. In some othercases, the representative point is chosen based on the mean or averageposition determined in act S111. For example, the representative pointmay be a location point of the vehicle-common or user-common locationdata (as projected on the line) that is closest to the mean or averageposition.

In act S115, the location points of the vehicle-common or user-commonlocation data other than the representative point may be removed. Theserver 125 may be configured to remove the non-representativevehicle-common or user-common location points via instructions stored inthe memory 803 and executed by the processor 801. Additionally oralternatively, the location data processor 905 may be configured toremove the location points of the vehicle-common or user-common locationdata other than the representative point. By choosing a representativepoint and discarding the rest of the location data generated by aparticular vehicle or user, the accuracy and efficiency of theclustering may be improved. For example, having fewer location points togroup into clusters may reduce the time needed to create the cluster. Inanother example, keeping only the representative point may preventpotentially erroneous location points from being clustered, therebyimproving a correspondence between a number of clusters determined forthe path and the number of lanes on the path. Also, a slow-movingvehicle, user, or mobile device will contribute more to the density ascompared to a faster moving vehicle, user, or mobile device on the samepath. Choosing a representative point may ensure that only one point pervehicle, user, or mobile device contributes to the density of the totalpoints.

In act S117, a standard deviation may be determined for the locationdata as projected onto the aggregation axis. The server 125 may beconfigured to determine the standard deviation via instructions storedin the memory 803 and executed by the processor 801. Additionally oralternatively, the statistics processor 907 may be configured todetermine the standard deviation. The standard deviation may bedetermined for the lateral positions of the location points on theaggregation axis. The standard deviation may be found my finding a meanposition of the location data on the aggregation axis, finding adifference between each location point and the mean, squaring thedifferences, adding the differences together, dividing by one less thana number (e.g. a count) of the location points, and taking the squareroot of the result. Where the standard deviation is smaller than thetypical width of a single lane road, it may be determined that the pathhas only a single lane. In this case, it may not be necessary to clusterthe location data to determine the number of lanes.

In act S119, a linear range is determined along the aggregation axis.The server 125 may be configured to determine the linear range viainstructions stored in the memory 803 and executed by the processor 801.Additionally or alternatively, the statistics processor 907 may beconfigured to determine the linear range. A width of the linear rangemay be based on the mean and the standard deviation determined for thelocation data as projected on the aggregation axis. In some cases, thelinear range may extend to a distance of a multiple of a standarddeviation beyond the mean. For example, the linear range may extend 1.5standard deviations beyond the mean.

In act S121, an outlier subset of the location data may be removed. Theserver 125 may be configured to remove outlier location data viainstructions stored in the memory 803 and executed by the processor 801.Additionally or alternatively, the location data processor 905 may beconfigured to remove outliers. The outlier subset may be those locationpoints of the location data outside of the linear range. The remaininglocation points after removal of the outlier subset may be a remainder.Removing the outlier points may help improve the efficiency and accuracyof clustering.

In act S123, a density of the location data along the aggregation axismay be determined. The server 125 may be configured to determine thedensity via instructions stored in the memory 803 and executed by theprocessor 801. Additionally or alternatively, the statistics processor907 may be configured to determine the density. The density may be ameasure of the number of location points per unit length along theaggregation line. Determining the linear density along the aggregationaxis may help identify regions of lower density. Such low-densityregions may correspond to gaps between lanes.

In act S125, location data is removed based on the density. The server125 may be configured to remove location points based on the density viainstructions stored in the memory 803 and executed by the processor 801.Additionally or alternatively, the location data processor 905 may beconfigured to remove location data based on the density. For example, athreshold minimum density may be specified. Location points residing insections of the aggregation axis having a density below the thresholdmay be removed. Because low-density may indicate a gap between vehiclesor users traveling in a lane, the location data may be removed fromlower-density areas because the location points in such areas may beerroneous. For example, the location data points between lanes may bedue to an error in the positioning system or due to a vehicle or userchanging lanes. In another example, a method like Local Outlier Factor(LOF) can be used.

In act S127, the location data may be grouped into clusters. The server125 may be configured to group the location data into clusters viainstructions stored in the memory 803 and executed by the processor 801.Additionally or alternatively, the aggregator 911 may be configured togroup the location data into clusters. The location data may be theremaining data after location data points were removed in one or more ofacts S115, S121, and S125. The location data as projected onto theaggregation axis may be grouped into clusters. Where there are multipleaggregation axes, for example where the path has been broken into pathsegments, the location data on each aggregation axis may be grouped intoclusters. The location data may be clustered by applying a clusteringmethod to the location data. For example, DBSCAN or HDBSCAN may be used.

Multiple sets of clusters may be generated according to differentcluster criteria. For example, with DBSCAN, different clusteringscenarios are possible by changing the cluster criteria for a corepoint: the size (distance) of a neighborhood and the minimum number ofpoints in the neighborhood. Creating different sets of clusters based ondifferent cluster criteria may allow for more accurate determination ofthe number of lanes on the path. In some cases, the multiple clustersmay be displayed on a display 71 or input device such as a personalcomputer or terminal 807. In some other cases, the cluster criteria maybe selected based on input from an input device 703, 807.

In act S129, a degree of overlap of the clusters may be determined. Theserver 125 may be configured to determine a measure of overlap betweenthe clusters via instructions stored in the memory 803 and executed bythe processor 801. Additionally or alternatively, the statisticsprocessor 907 may be configured to determine a measure of overlapbetween the clusters. Cluster overlap may be measured by determining asilhouette coefficient. The overlap may be determined for each set ofclusters from act S127 according to different cluster criteria.

In act S131, a silhouette coefficient is determined. The server 125 maybe configured to determine the silhouette coefficient via instructionsstored in the memory 803 and executed by the processor 801. Additionallyor alternatively, the statistics processor 907 may be configured todetermine the silhouette coefficient. The silhouette coefficient maytake into account a measure of the distance between a location point andevery other location point in the same cluster and also a measure of thedistance between the location point and other location points in otherclusters. The clusters have little overlap and are very distinct whenthe silhouette coefficient approaches 1, and more overlap when thesilhouette coefficient approaches −1. The silhouette coefficient may bedetermined for each set of clusters grouped according to differentcluster criteria.

In act S133, a grouping or set of clusters is chosen based on minimizingoverlap between clusters. For example, a set of clusters having ahighest overall silhouette coefficient for the location points may bechosen. The server 125 may be configured to choose the grouping or setof clusters via instructions stored in the memory 803 and executed bythe processor 801. Additionally or alternatively, the geographic dataprocessor 913 may be configured to choose the grouping or set ofclusters. In some cases, the grouping or set of clusters may be chosenbased on input from an input device 703, 807.

In act S135, a number of lanes is determined for the path based on thenumber of clusters. For example, where three clusters are formed fromthe location data, the path may be determined to have three lanes. Theserver 125 may be configured to determine the number of lanes viainstructions stored in the memory 803 and executed by the processor 801.The server 125 may update the database 123 with the number of lanes forthe path. Additionally or alternatively, the geographic data processor913 may be configured to determine the number of lanes. Where the pathhas been split into segments, the number of lanes for the whole pathincluding all the segments may be based on a number of clusters formedby a majority of the segments. For example, where a majority of thesegments have location data grouped into five lanes, the whole path maybe determined to have five lanes. Where there is no majority, the numberof lanes may be chosen based on an average number of lanes or based onanother method.

FIG. 6 illustrates another example system for collecting location data.The system may include one or more positioning sensors 101 incommunication with a mobile device 122 and vehicle 124 traversing a path601.

The positioning sensor 101 may be in communication with or a part of themobile device 122 or the vehicle 124. The positioning sensor 101 maymeasure a location of the vehicle 124 or the mobile device 122 as thevehicle 124 or the mobile device 122 traverse the path 601. Thepositioning sensor 101 may generate location information includingmultiple measurements of the location of the vehicle 124 or the mobiledevice 122. The measurements may be location points indicating themeasured positions of the vehicle 124 or the mobile device 122. Thepositioning sensor 101 may send the location information including oneor more location points to the mobile device 122 or the vehicle 124.

The mobile device 122 may receive a stream of location information fromthe positioning sensor 101. For example, the positioning sensor 101 mayperiodically measure the location of the mobile device 122 as ittraverses the path 601. The mobile device 122 may send the locationinformation to the server 125 of FIG. 1. The mobile device 122. maybelong to or be associated with a user.

The vehicle 124 may receive a stream of location information from thepositioning sensor 101. For example, the positioning sensor 101 mayperiodically measure the location of the vehicle 124 as it traverses thepath 601. The vehicle 124 may send the location information to theserver 125 of FIG. 1.

The path 601 is a path traversed by the mobile device 122 or the vehicle124. The database 123 of FIG. 1 may store information about the path.For example, the path may have a number of lanes of traffic and thenumber of lanes may be stored in the database 123. The server 125 may beconfigured to determine the number of lanes of traffic on the path 601based on location information generated by position sensors 101 on thepath 601. For example, location information from both vehicles 124 shownmay be used by the server 125 to determine that there are two lanes oftraffic on the path. The path may have more or fewer lanes of traffic.

FIG. 7 illustrates a further example system for collecting locationdata. The system may include a mobile device 122, for example, asdescribed in FIGS. 1 and 6. The Mobile device 122 may include aprocessor 701, an input device 703, a communication interface 705, anetwork interface 707, a memory 709, a display 711, and a positioncircuitry 713. Different or fewer components may be present. Forexample, the mobile device 122 may not include position circuitry 713.In another example, the network interface is part of the communicationinterface 705.

The processor 701 may be a general processor or application specificintegrated circuit. The processor 701 may retrieve or receiveinstructions stored in the memory 709 and execute the instructions.

The input device 703 may be used for interacting with the mobile device122 or to change settings of the mobile device 122. For example, theinput device 703 may be used to interact with an application of themobile device 122, such as a mapping or navigation application. Inanother example, the input device 703 may be used to specify a settingof the position circuitry 713. The input device 703 may be used tospecify the interval at which the position circuitry measures a locationof the mobile device 122.

The communication interface 705 may provide for the exchange ofinformation between the mobile device 122 and outside systems. Forexample, the communication interface 705 may form a connection to one ormore position sensors or other sensors that are external to the mobiledevice 122. In another example, the communication interface may form aconnection between the mobile device and a vehicle. In this way, themobile device may send and receive data to the sensors and vehiclesexternal to the mobile device. For example, the mobile device mayreceive location information from a position sensor that is part of thevehicle.

The network interface 707 may form a connection to the network 107. Forexample, the network interface 707 may be coupled with antennas fortransmitting and receiving data. In some cases, the network interface707 forms a connection to the network 107. In this way, the networkinterface 707 may allow for the exchange of data between the mobiledevice 122 and the server 125 or the database 123. In some cases, thenetwork interface 707 may be a part of the communication interface 705.

The memory 709 may be a volatile memory or a non-volatile memory. Thememory 709 may include one or more of a read only memory (ROM), randomaccess memory (RAM), a flash memory, an electronic erasable program readonly memory (EEPROM), or other type of memory. The memory 709 may beremovable from the mobile device 122, such as a secure digital (SD)memory card. The memory 709 may store instructions to cause theprocessor 701 to perform one or more acts. The memory may be configuredto store location information from the position circuitry 713 or apositioning sensor.

The display 711 may be a liquid crystal display (LCD) panel, lightemitting diode (LED) screen, thin film transistor screen, or anothertype of display. An output interface of the display 711 may also includeaudio capabilities, or speakers. The display 711 may indicate a statusor other information about the mobile device 122, the positioningcircuitry 713, or a positioning sensor in communication with the mobiledevice 122. The display 711 may display mapping or navigationinformation. For example, a navigation or mapping application on themobile device 122 may use the display to present mapping or navigationinformation.

The position circuitry 713 may be a positioning sensor. For example, theposition circuitry may use GPS or GNSS to measure its location. In somecases, the position circuitry 713 may be remote from the mobile device122. The position circuitry 713 may communicate with the processor 701directly or through one or more intermediaries. For example, theposition circuitry may communicate with the processor 701 of the mobiledevice 122 through the communication interface 705. The positioncircuitry 713 may measure a location of the mobile device 122. In somecases, the position circuitry 713 measures the location of the mobiledevice 122 periodically or at a predetermined interval. The positioncircuitry 713 may be configured to send the measured location to themobile device 122, for example to the processor 701. The locationinformation generated by the position circuitry 713 may be sent to theserver 125.

FIG. 8 illustrates an example server 125. The server 125 may be theserver 125 of FIG. 1. The server 125 may include a processor 801, amemory 803, a communication interface 805, and an input device 807. Theserver 125 may be in communication with a database 123.

The processor 801 may be a general processor or application specificintegrated circuit. The processor 801 may retrieve or receiveinstructions stored in the memory 803 and execute the instructions.

The memory 803 may be a volatile memory or a non-volatile memory. Thememory 803 may include one or more of a read only memory (ROM), randomaccess memory (RAM), a flash memory, an electronic erasable program readonly memory (EEPROM), or other type of memory. The memory 803 may beremovable from the server 125, such as a secure digital (SD) memorycard. The memory 803 may store instructions to cause the processor 801to perform one or more acts. The memory may be configured to storelocation information from the position circuitry 713 or a positioningsensor.

The communication interface 805 may provide a connection between theserver 125 and the network 107. In some cases, the communicationinterface 805 may facilitate the receipt of the location informationfrom the mobile device 122 or the vehicle 124.

The input device 807 may be a keyboard, terminal, or personal computer.The input device may be used to enter or modify settings of the server125. For example, the setting may include one or more cluster criteria.In another example, the settings including selection of a particularpath for which a number of lanes is to be determined. In some cases, theinput device may be used to select one or more location informationpreprocessing steps, such as density-based location data removal,standard deviation-based location data removal, or vehicle-common oruser-common location data removal.

The database 123 may be directly connected to the server 125 oraccessible though a network 107. For example, the server 125 maycommunicate with the database 123 through the communication interface805. In some cases, the database may be stored in the memory 803. Thedatabase 123 may be configured to store location information.

FIG. 9 illustrates an example system for assigning a number of lanes ona path. The system may include a lane count estimator 901. The lanecount estimator may include a receiver 903, a location data processor905, a statistics processor 907, a vehicle path processor 909, anaggregator 911, and a geographic data processor. More, different, orfewer components may be provided. The lane count estimator 901 may beimplemented by the server 125 of FIGS. 1 and 8 or by another computingdevice remote to the mobile device 122 and vehicle 124.

The receiver 903 be configured for digital or analog communication withone or more position sensors. For example, the receiver 903 may beconfigured to receive location information from one or more positionsensors through the network 107. The receiver may be implemented by or apart of the communication interface 805 of the server 125. The receiver903 may include one or more amplifiers, digital to analog converters, oranalog to digital converters. The location data received by the receivermay include a plurality of location points recorded by one or morevehicles or mobile devices.

The location data processor 905 may be implemented by the processor 801based on instructions stored in the memory 803 of the server 125. Thelocation data processor 905 may be configured to remove a portion of thelocation data. For example, the location data processor may beconfigured to remove a number of location data points in the locationdata that were generated by the same vehicle, user, or mobile device.The location data points generated by the same vehicle, user, or mobiledevice may be referred to as vehicle-common or user-common because eachof the location points is associated with a common vehicle, user, ormobile device. The location data processor 905 may be configured todetermine a representative point of the vehicle-common or user-commonlocation points and to remove the rest of the vehicle-common oruser-common location points (e.g. those location points not selected asthe representative point) from the location data. The location dataprocessor 905 may be configured to select the representative point basedon a centroid of the vehicle-common or user-common location points. Forexample, the representative point may be the vehicle-common oruser-common location point closest to the centroid. Additionally oralternatively, where the vehicle-common or user-common location pointsare projected on a line perpendicular to a centerline of the path, therepresentative point may be the vehicle-common or user-common locationpoint closest to a mean of the vehicle-common or user-common locationpoints. Where the location data includes multiple sets of vehicle-commonor user-common location points (e.g. a plurality of vehicles each havinggenerated more than one location point along the path), the selection ofthe representative point and removal of the non-selected points may berepeated for each set of vehicle-common or user-common location points.

The location data processor 905 may be configured to perform standarddeviation-based outlier removal on the location data. The outliers maybe the portion of the location data removed by the location dataprocessor 905. A linear range may be defined (e.g. by the statisticprocessor 907) for the location data projected onto the aggregationaxis. The linear range may be based on a standard deviation and/or themean of the location data. The location data processor 905 may beconfigured to remove the location points that lie outside of the linearrange from the location data. The location points that lie outside ofthe linear range may be referred to as an outlier subset of locationdata.

The location data processor 905 may be configured to performdensity-based outlier removal on the location data. The outliers may bethe portion of the location data removed by the location data processor905. A minimum threshold density may be defined below which locationdata is to be excluded. Removing location points lying in less denseareas may more clearly define the lanes present on the path aftergrouping the location data into clusters. The location data processor905 may be configured to remove those location points residing in alinear space having below the minimum threshold density. The density maybe defined as a minimum number of location points per unit distance. Forexample, the minimum threshold density may be 1 location point permeter. Where a location data point is more than 0.5 meters from itsnearest neighboring location data points (e.g. the location point is theonly location point located on a section of the aggregation axis longerthan 1 meter, or the distance from the nearest neighbor to the right ofthe location data point to the nearest neighbor to the left of thelocation data point is greater than 1 meter), the location dataprocessor 905 may be configured to remove the location point.

The location data processor 905 may be configured to select a groupingor arrangement of clusters of the location data based on a degree ofoverlap determined for the clusters. For example, where multiplearrangements or sets of clusters of the location data have beengenerated based on multiple cluster criteria, the location dataprocessor 905 may select an arrangement or set of clusters with theleast or minimal overlap between clusters. Minimizing cluster overlapmay improve correspondence between a number of clusters and a number oflanes for the path.

The statistics processor 907 may be implemented by the processor 801based on instructions stored in the memory 803 of the server 125. Thestatistics processor 907 may be configured to determine one or moremathematical quantities of the location data. For example, thestatistics processor 907 may be configured to determine a mathematicalquantity such as a standard deviation of the location information. Insome cases, the statistics processor 907 may determine a standarddeviation of the location data as projected on the aggregation axis. Insome cases, the statistics processor 907 may be configured to determinea mean or average lateral position of the location data as projected onthe aggregation axis. Based on the standard deviation and/or the mean,the statistics processor 907 may configured to determine a linear rangeon the aggregation axis. For example, the linear range may extend at awidth of one standard deviation on either side of the mean. In anotherexample, the linear range extends 1.5 standard deviations on either sideof the mean. Other multiples of the standard deviation may be used todefine the linear range. The width of the linear range may correspond toa width of the path. For example, the linear range may be chosen to besmaller than the width of the path. Location data points located outsideof the linear range may be removed or discarded from the location dataprior to grouping into clusters.

The statistics processor 907 may be configured to determine amathematical quantity such as a mean of vehicle-common or user-commonlocation points as projected onto a line perpendicular to the centerlineof the path. The mean may be used by the location data processor to picka representative point.

The statistics processor 907 may be configured to determine amathematical quantity such as a centroid of vehicle-common oruser-common location points. The centroid may be defined as a point thatminimizes the sum of squared distances between the centroid and thevehicle-common or user-common location points (for a particular vehicle,user, or mobile device). The centroid may be determined for each set ofvehicle-common or user-common location points where the location dataincludes multiple location points from multiple, vehicles, users, ormobile devices.

The statistics processor 907 may be configured to determine amathematical quantity such as a density of the location points asprojected on the aggregation axis. The density may be defined as anumber of location points per linear unit of distance along theaggregation axis. The density may be defined for subsections of theaggregation axis. In some cases, the density may be determined for eachspan of 0.1 meters along the aggregation axis. For example, where a spanof the aggregation axis is 0.1 meters wide and includes 2 locationpoints, the density on the subsection of the aggregation axis may bedetermined to be 20 points per meter. Spans of the aggregation axishaving below a threshold density may be removed from the location data.

The statistics processor 907 may be configured to determine amathematical quantity such as a degree of overlap between clusters oflocation data. The degree of overlap may be measured or indicated by asilhouette coefficient or another measure. The degree of cluster overlapmay be determined for each set or arrangement of clusters when multiplesets or arrangements of clusters have been generated according tomultiple cluster criteria.

The vehicle path processor 909 may be implemented by the processor 801based on instructions stored in the memory 803 of the server 125. Thevehicle path processor 909 may be configured to linearize a curve of apath. For example, the vehicle path processor 909 may fit one or morelinear path segments to the path. The path segments may be fit to acenterline or other part of the path. An optimal fit may reduce anydeviation by the path segments from the path. Together, the one or morepath segments may form a linear approximation of the path. When the pathhas been approximated, segmented into, or otherwise represented by pathsegments, the vehicle path processor 909 may be configured to matchsubsets of the location data to the segments. In some cases, a locationpoint of the location data may be matched to whichever path segment isclosest to the location point. Each location point of the location datamay be matched to a single path segment so that a non-overlapping subsetof the location data is associated with each path segment (e.g. eachlocation point is only associated with a single path segment).

The aggregator 911 may be implemented by the processor 801 based oninstructions stored in the memory 803 of the server 125. The aggregator911 may be configured to project the location points of the locationdata onto the aggregation axis. The aggregation axis may be defined as aline perpendicular to a centerline of the path. The aggregator 911 maybe configured to project only those location points that remain in thelocation data. In some cases, location points removed because ofdensity, standard deviation, or in the process of defining arepresentative point may not be projected. For example, only locationpoints that are not part of the outlier subset of location data may beprojected. In some cases, the aggregator 911 may be configured toproject the vehicle-common or user-common location points onto a lineperpendicular to the centerline of the path.

The aggregator 911 may be configured to group the location pointsprojected onto the aggregation axis into one or more clusters. Theaggregator 911 may use a clustering method such as DBSCAN or HDBSCAN tocluster the location data. The aggregator 911 may be configured togenerate multiple sets or arrangements of clusters by varying clustercriteria. For example, the neighborhood distance and minimum number ofpoints in a core point neighborhood may be varied by the aggregator 911to obtain different set or arrangements of clusters. Changing theclustering criteria may result in different location points beinggrouped into different clusters. In some cases, the cluster criteria maybe changed or selected based on input from an input device 703, 807. Theaggregator 911 may be configured to perform clustering for each pathsegment on the subset of location points associated with each pathsegment.

The geographic data processor 913 may be implemented by the processor801 based on instructions stored in the memory 803 of the server 125.The geographic data processor 913 may be configured to determine anumber of lanes present on a path segment. The number of lanes may rangefrom a single lane to 10 or more lanes. Additionally or alternatively,the orientation of the lanes may be determined. For example, a directionof travel of vehicles, users, or mobile devices contributing to thelocation data may be used as a direction of travel for the lanes. Thegeographic data processor 913 may determine the number of lanes based onthe number of clusters of location data for the path. For example, wherethe location data for a path is grouped into three clusters, thegeographic data processor 913 may determine that the path has 3 lanes.The geographic data processor 913 may update a record of the path storedin the database 123 with the number of lanes. When multiple cluster setsor arrangements have been generated for a path, the geographic dataprocessor 913 may use the cluster set or arrangement with the leastamount of overlap. The geographic data processor 913 may be configuredto determine a number of lanes for each path segment of a path. Thenumber of lanes for the whole path may be determined based on the numberof lanes for each segment. A “majority vote” of the number of lanes forthe path segments may be used to determine the number of lanes for thewhole path. For example, where there are five path segments and threesegments have been determined to have two lanes, the geographic dataprocessor 913 may determine that the whole path has two lanes.

FIG. 10 illustrates an example geographic database. The geographicdatabase 123 may contain at least one road segment database record 304(also referred to as “entity” or “entry”) for each road segment in aparticular geographic region. The geographic database 123 may alsoinclude a node database record 306 (or “entity” or “entry”) for eachnode in a particular geographic region. The terms “nodes” and “segments”represent only one terminology for describing these physical geographicfeatures, and other terminology for describing these features isintended to be encompassed within the scope of these concepts. Thegeographic database 123 may also include location fingerprint data forspecific locations in a particular geographic region.

The geographic database 123 may include other kinds of data 310. Theother kinds of data 310 may represent other kinds of geographic featuresor anything else. The other kinds of data may include point of interest(POI) data. For example, the POI data may include POI records comprisinga type (e.g., the type of POI, such as restaurant, hotel, city hall,police station, historical marker, ATM, golf course, etc.), location ofthe POI, a phone number, hours of operation, etc.

The geographic database 123 also includes indexes 314. The indexes 314may include various types of indexes that relate the different types ofdata to each other or that relate to other aspects of the data containedin the geographic database 123. For example, the indexes 314 may relatethe nodes in the node data records 306 with the end points of a roadsegment in the road segment data records 304.

The geographic database 123 may also include other attributes of orabout roads such as, for example, geographic coordinates, physicalgeographic features (e.g., lakes, rivers, railroads, municipalities,etc.) street names, address ranges, speed limits, turn restrictions atintersections, and/or other navigation related attributes (e.g., one ormore of the road segments is part of a highway or toll way, the locationof stop signs and/or stoplights along the road segments), as well asPOIs, such as gasoline stations, hotels, restaurants, museums, stadiums,offices, automobile dealerships, auto repair shops, buildings, stores,parks, municipal facilities, other businesses, etc. The geographicdatabase 123 may also contain one or more node data record(s) 306 whichmay be associated with attributes (e.g., about the intersections) suchas, for example, geographic coordinates, street names, address ranges,speed limits, turn restrictions at intersections, and other navigationrelated attributes, as well as POIs such as, for example, gasolinestations, hotels, restaurants, museums, stadiums, offices, automobiledealerships, auto repair shops, buildings, stores, parks, etc. Thegeographic data 302 may additionally or alternatively include other datarecords such as, for example, POI data records, topographical datarecords, cartographic data records, routing data, and maneuver data.Other contents of the database 123 may include temperature, altitude orelevation, lighting, sound or noise level, humidity, atmosphericpressure, wind speed, the presence of magnetic fields, electromagneticinterference, or radio- and micro-waves, cell tower and wi-fiinformation, such as available cell tower and wi-fi access points, andattributes pertaining to specific approaches to a specific location.

The geographic database 123 may include historical traffic speed datafor one or more road segments. The geographic database 123 may alsoinclude traffic attributes for one or more road segments. A trafficattribute may indicate that a road segment has a high probability oftraffic congestion.

FIG. 11 shows some of the components of a road segment data record 304contained in the geographic database 123 according to one embodiment.The road segment data record 304 may include a segment ID 304(1) bywhich the data record can be identified in the geographic database 123.Each road segment data record 304 may have associated information (suchas “attributes”, “fields”, etc.) that describes features of therepresented road segment. The road segment data record 304 may includedata 304(2) that indicate the restrictions, if any, on the direction ofvehicular travel permitted on the represented road segment. The roadsegment data record 304 may include data 304(3) that indicate a speedlimit or speed category (i.e., the maximum permitted vehicular speed oftravel) on the represented road segment. The road segment data record304 may also include classification data 304(4) indicating whether therepresented road segment is part of a controlled access road (such as anexpressway), a ramp to a controlled access road, a bridge, a tunnel, atoll road, a ferry, and so on. The road segment data record may includelocation fingerprint data, for example a set of sensor data for aparticular location.

The geographic database 123 may include road segment data records 304(or data entities) that describe features such as road objects 304(5).The road objects 304(5) may be stored according to location boundariesor vertices. The road objects 304(5) may be stored as a field or recordusing a scale of values such as from 1 to 100 for type or size. The roadobjects 304(5) may be stored using categories such as low, medium, orhigh. Additional schema may be used to describe the road objects 304(5).The attribute data may be stored in relation to a link/segment 304, anode 306, a strand of links, a location fingerprint, an area, or aregion. The geographic database 123 may store information or settingsfor display preferences. The geographic database 123 may be coupled to adisplay. The display may be configured to display the roadway networkand data entities using different colors or schemes.

The road segment data record 304 may include a lane count 304(6) for theroad segment. The lane count 304(6) may be a numerical value indicatingthe number of lanes of the road segment. The lane count 304(6) mayindicate the number of lanes for the whole width of the road segment orfor one direction of travel along the road segment. In some cases, theroad segment data record 304 includes a lane count 304(6) for eachdirection of travel along the road segment.

The road segment data record 304 also includes data 304(7) providing thegeographic coordinates (e.g., the latitude and longitude) of the endpoints of the represented road segment. In one embodiment, the data304(7) are references to the node data records 306 that represent thenodes corresponding to the end points of the represented road segment.

The road segment data record 304 may also include or be associated withother data 304(7) that refer to various other attributes of therepresented road segment. The various attributes associated with a roadsegment may be included in a single road segment record or may beincluded in more than one type of record which cross-references to eachother. For example, the road segment data record 304 may include dataidentifying what turn restrictions exist at each of the nodes whichcorrespond to intersections at the ends of the road portion representedby the road segment, the name, or names by which the represented roadsegment is identified, the street address ranges along the representedroad segment, and so on.

FIG. 9 also shows some of the components of a node data record 306 thatmay be contained in the geographic database 123. Each of the node datarecords 306 may have associated information (such as “attributes”,“fields”, etc.) that allows identification of the road segment(s) thatconnect to it and/or its geographic position (e.g., its latitude andlongitude coordinates). The node data records 306(1) and 306(2) includethe latitude and longitude coordinates 306(1)(1) and 306(2)(1) for theirnode. The node data records 306(1) and 306(2) may also include otherdata 306(1)(2) and 306(2)(2) that refer to various other attributes ofthe nodes.

The geographic database 123 may be maintained by a content provider(e.g., a map developer). By way of example, the map developer maycollect geographic data to generate and enhance the geographic database123. The map developer may obtain data from sources, such as businesses,municipalities, or respective geographic authorities. In addition, themap developer may employ field personnel to travel throughout ageographic region to observe features and/or record information aboutthe roadway. Remote sensing, such as aerial or satellite photography,may be used

The geographic database 123 and the data stored within the geographicdatabase 123 may be licensed or delivered on-demand. Other navigationalservices or traffic server providers may access the location fingerprintdata, traffic data and/or the lane line object data stored in thegeographic database 123.

The mobile device 122, server 125, or processors 701, 801 may include ageneral processor, digital signal processor, an application specificintegrated circuit (ASIC), field programmable gate array (FPGA), analogcircuit, digital circuit, combinations thereof, or other now known orlater developed processor. The mobile device 122, server 125, orprocessors 701, 801 may be a single device or combinations of devices,such as associated with a network, distributed processing, or cloudcomputing.

The memory 709, 803 may be a volatile memory or a non-volatile memory.The memory 709, 803 may include one or more of a read only memory (ROM),random access memory (RAM), a flash memory, an electronic erasableprogram read only memory (EEPROM), or other type of memory. The memory709, 803 may be removable from the mobile device 122 or server 125, suchas a secure digital (SD) memory card.

The communication interface 705, 805 may include any operableconnection. An operable connection may be one in which signals, physicalcommunications, and/or logical communications may be sent and/orreceived. An operable connection may include a physical interface, anelectrical interface, and/or a data interface. The communicationinterface 705, 805 provides for wireless and/or wired communications inany now known or later developed format.

The databases 123 may include geographic data used for traffic and/ornavigation-related applications. The geographic data may include datarepresenting a road network or system including road segment data andnode data. The road segment data represent roads, and the node datarepresent the ends or intersections of the roads. The road segment dataand the node data indicate the location of the roads and intersectionsas well as various attributes of the roads and intersections. Otherformats than road segments and nodes may be used for the geographicdata. The geographic data may include structured cartographic data orpedestrian routes.

The databases may also include other attributes of or about the roadssuch as, for example, geographic coordinates, street names, addressranges, speed limits, turn restrictions at intersections, and/or othernavigation related attributes (e.g., one or more of the road segments ispart of a highway or toll way, the location of stop signs and/orstoplights along the road segments), as well as points of interest(POIs), such as gasoline stations, hotels, restaurants, museums,stadiums, offices, automobile dealerships, auto repair shops, buildings,stores, parks, etc. The databases may also contain one or more node datarecord(s) which may be associated with attributes (e.g., about theintersections) such as, for example, geographic coordinates, streetnames, address ranges, speed limits, turn restrictions at intersections,and other navigation related attributes, as well as POIs such as, forexample, gasoline stations, hotels, restaurants, museums, stadiums,offices, automobile dealerships, auto repair shops, buildings, stores,parks, etc. The geographic data may additionally or alternativelyinclude other data records such as, for example, POI data records,topographical data records, cartographic data records, routing data, andmaneuver data.

The databases may include historical traffic speed data for one or moreroad segments. The databases may also include traffic attributes for oneor more road segments. A traffic attribute may indicate that a roadsegment has a high probability of traffic congestion.

The input device 703, 807 may be one or more buttons, keypad, keyboard,mouse, stylus pen, trackball, rocker switch, touch pad, voicerecognition circuit, or other device or component for inputting data tothe mobile device 122 or server 125. The input device 703, 807 anddisplay 711 may be combined as a touch screen, which may be capacitiveor resistive. The display 711 may be a liquid crystal display (LCD)panel, light emitting diode (LED) screen, thin film transistor screen,or another type of display. The output interface of the display 711 mayalso include audio capabilities, or speakers. In an embodiment, theinput device 703, 807 may involve a device having velocity detectingabilities.

The positioning circuitry 713 or a position sensor may include suitablesensing devices that measure the traveling distance, speed, direction,and so on, of the vehicle 124 or mobile device 122. The positioningsystem may also include a receiver and correlation chip to obtain a GPSsignal. Alternatively or additionally, the one or more detectors orsensors may include an accelerometer and/or a magnetic sensor built orembedded into or within the interior of the vehicle 124 or mobile device122. The accelerometer is operable to detect, recognize, or measure therate of change of translational and/or rotational movement of thevehicle 124 or mobile device 122. The magnetic sensor, or a compass, isconfigured to generate data indicative of a heading of the vehicle 124or mobile device 122. Data from the accelerometer and the magneticsensor may indicate orientation of the vehicle 124 or mobile device 122.The vehicle 124 or mobile device 122 receive location data from thepositioning system. The location data indicates the location of thevehicle 124 or mobile device 122.

The positioning circuitry 713 or a position sensor may include a GlobalPositioning System (GPS), Global Navigation Satellite System (GLONASS),or a cellular or similar position sensor for providing location data.The positioning system may utilize GPS-type technology, a deadreckoning-type system, cellular location, or combinations of these orother systems. The positioning circuitry 713 or a position sensor mayinclude suitable sensing devices that measure the traveling distance,speed, direction, and so on, of the vehicle 124 or mobile device 122.The positioning system may also include a receiver and correlation chipto obtain a GPS signal. The vehicle 124 or mobile device 122 receiveslocation data from the positioning system. The location data indicatesthe location of the vehicle 124 or mobile device 122.

The positioning circuitry 713 or a position sensor may also includegyroscopes, accelerometers, magnetometers, or any other device fortracking or determining movement of a mobile device. The gyroscope isoperable to detect, recognize, or measure the current orientation, orchanges in orientation, of a mobile device. Gyroscope orientation changedetection may operate as a measure of yaw, pitch, or roll of the mobiledevice.

In accordance with various embodiments of the present disclosure, themethods described herein may be implemented by software programsexecutable by a computer system. Further, in an exemplary, non-limitedembodiment, implementations can include distributed processing,component/object distributed processing, and parallel processing.Alternatively, virtual computer system processing can be constructed toimplement one or more of the methods or functionalities as describedherein.

Although the present specification describes components and functionsthat may be implemented in particular embodiments with reference toparticular standards and protocols, the invention is not limited to suchstandards and protocols. For example, standards for Internet and otherpacket switched network transmission (e.g., TCP/IP, UDP/IP, HTML, HTTP,HTTPS) represent examples of the state of the art. Such standards areperiodically superseded by faster or more efficient equivalents havingessentially the same functions. Accordingly, replacement standards andprotocols having the same or similar functions as those disclosed hereinare considered equivalents thereof.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, and it can bedeployed in any form, including as a standalone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

The processes and logic flows described in this specification can beperformed by one or more programmable processors executing one or morecomputer programs to perform functions by operating on input data andgenerating output. The processes and logic flows can also be performedby, and apparatus can also be implemented as, special purpose logiccircuitry, e.g., an FPGA (field programmable gate array) or an ASIC(application specific integrated circuit).

As used in this application, the term ‘circuitry’ or ‘circuit’ refers toall of the following: (a) hardware-only circuit implementations (such asimplementations in only analog and/or digital circuitry) and (b) tocombinations of circuits and software (and/or firmware), such as (asapplicable): (i) to a combination of processor(s) or (ii) to portions ofprocessor(s)/software (including digital signal processor(s)), software,and memory(ies) that work together to cause an apparatus, such as amobile phone or server, to perform various functions) and (c) tocircuits, such as a microprocessor(s) or a portion of amicroprocessor(s), that require software or firmware for operation, evenif the software or firmware is not physically present.

This definition of ‘circuitry’ applies to all uses of this term in thisapplication, including in any claims. As a further example, as used inthis application, the term “circuitry” would also cover animplementation of merely a processor (or multiple processors) or portionof a processor and its (or their) accompanying software and/or firmware.The term “circuitry” would also cover, for example and if applicable tothe particular claim element, a baseband integrated circuit orapplications processor integrated circuit for a mobile phone or asimilar integrated circuit in server, a cellular network device, orother network device.

Processors suitable for the execution of a computer program include, byway of example, both general and special purpose microprocessors, andanyone or more processors of any kind of digital computer. Generally, aprocessor receives instructions and data from a read only memory or arandom-access memory or both. The essential elements of a computer are aprocessor for performing instructions and one or more memory devices forstoring instructions and data. Generally, a computer also includes, orbe operatively coupled to receive data from or transfer data to, orboth, one or more mass storage devices for storing data, e.g., magnetic,magneto optical disks, or optical disks. However, a computer need nothave such devices. Moreover, a computer can be embedded in anotherdevice, e.g., a mobile telephone, a personal digital assistant (PDA), amobile audio player, a Global Positioning System (GPS) receiver, to namejust a few. Computer readable media suitable for storing computerprogram instructions and data include all forms of non-volatile memory,media, and memory devices, including by way of example semiconductormemory devices, e.g., EPROM, EEPROM, and flash memory devices; magneticdisks, e.g., internal hard disks or removable disks; magneto opticaldisks; and CD ROM and DVD-ROM disks. The processor and the memory can besupplemented by, or incorporated in, special purpose logic circuitry. Inan embodiment, a vehicle may be considered a mobile device, or themobile device may be integrated into a vehicle.

To provide for interaction with a user, embodiments of the subjectmatter described in this specification can be implemented on a devicehaving a display, e.g., a CRT (cathode ray tube) or LCD (liquid crystaldisplay) monitor, for displaying information to the user and a keyboardand a pointing device, e.g., a mouse or a trackball, by which the usercan provide input to the computer. Other kinds of devices can be used toprovide for interaction with a user as well; for example, feedbackprovided to the user can be any form of sensory feedback, e.g., visualfeedback, auditory feedback, or tactile feedback; and input from theuser can be received in any form, including acoustic, speech, or tactileinput.

The term “computer-readable medium” includes a single medium or multiplemedia, such as a centralized or distributed database, and/or associatedcaches and servers that store one or more sets of instructions. The term“computer-readable medium” shall also include any medium that is capableof storing, encoding, or carrying a set of instructions for execution bya processor or that cause a computer system to perform any one or moreof the methods or operations disclosed herein.

In a particular non-limiting, exemplary embodiment, thecomputer-readable medium can include a solid-state memory such as amemory card or other package that houses one or more non-volatileread-only memories. Further, the computer-readable medium can be arandom-access memory or other volatile re-writable memory. Additionally,the computer-readable medium can include a magneto-optical or opticalmedium, such as a disk or tapes or other storage device to capturecarrier wave signals such as a signal communicated over a transmissionmedium. A digital file attachment to an e-mail or other self-containedinformation archive or set of archives may be considered a distributionmedium that is a tangible storage medium. Accordingly, the disclosure isconsidered to include any one or more of a computer-readable medium or adistribution medium and other equivalents and successor media, in whichdata or instructions may be stored. These examples may be collectivelyreferred to as a non-transitory computer readable medium.

In an alternative embodiment, dedicated hardware implementations, suchas application specific integrated circuits, programmable logic arraysand other hardware devices, can be constructed to implement one or moreof the methods described herein. Applications that may include theapparatus and systems of various embodiments can broadly include avariety of electronic and computer systems. One or more embodimentsdescribed herein may implement functions using two or more specificinterconnected hardware modules or devices with related control and datasignals that can be communicated between and through the modules, or asportions of an application-specific integrated circuit.

Embodiments of the subject matter described in this specification can beimplemented in a computing system that includes a back end component,e.g., as a data server, or that includes a middleware component, e.g.,an application server, or that includes a front end component, e.g., aclient computer having a graphical user interface or a Web browserthrough which a user can interact with an implementation of the subjectmatter described in this specification, or any combination of one ormore such back end, middleware, or front end components. The componentsof the system can be interconnected by any form or medium of digitaldata communication, e.g., a communication network. Examples ofcommunication networks include a local area network (“LAN”) and a widearea network (“WAN”), e.g., the Internet.

The computing system can include clients and servers. A client andserver are generally remote from each other and typically interactthrough a communication network. The relationship of client and serverarises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other.

The illustrations of the embodiments described herein are intended toprovide a general understanding of the structure of the variousembodiments. The illustrations are not intended to serve as a completedescription of all of the elements and features of apparatus and systemsthat utilize the structures or methods described herein. Many otherembodiments may be apparent to those of skill in the art upon reviewingthe disclosure. Other embodiments may be utilized and derived from thedisclosure, such that structural and logical substitutions and changesmay be made without departing from the scope of the disclosure.Additionally, the illustrations are merely representational and may notbe drawn to scale. Certain proportions within the illustrations may beexaggerated, while other proportions may be minimized. Accordingly, thedisclosure and the figures are to be regarded as illustrative ratherthan restrictive.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of the invention or of what may beclaimed, but rather as descriptions of features specific to particularembodiments of the invention. Certain features that are described inthis specification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable sub-combination. Moreover, although features may be describedabove as acting in certain combinations and even initially claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a sub-combination or variation of a sub-combination.

Similarly, while operations are depicted in the drawings and describedherein in a particular order, this should not be understood as requiringthat such operations be performed in the particular order shown or insequential order, or that all illustrated operations be performed, toachieve desirable results. In certain circumstances, multitasking andparallel processing may be advantageous. Moreover, the separation ofvarious system components in the embodiments described above should notbe understood as requiring such separation in all embodiments.

One or more embodiments of the disclosure may be referred to herein,individually and/or collectively, by the term “invention” merely forconvenience and without intending to voluntarily limit the scope of thisapplication to any particular invention or inventive concept. Moreover,although specific embodiments have been illustrated and describedherein, it should be appreciated that any subsequent arrangementdesigned to achieve the same or similar purpose may be substituted forthe specific embodiments shown. This disclosure is intended to cover anyand all subsequent adaptations or variations of various embodiments.Combinations of the above embodiments, and other embodiments notspecifically described herein, are apparent to those of skill in the artupon reviewing the description.

The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b) and is submitted with the understanding that it will not be usedto interpret or limit the scope or meaning of the claims. In addition,in the foregoing Detailed Description, various features may be groupedtogether or described in a single embodiment for the purpose ofstreamlining the disclosure. This disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter may be directed toless than all of the features of any of the disclosed embodiments. Thus,the following claims are incorporated into the Detailed Description,with each claim standing on its own as defining separately claimedsubject matter.

It is intended that the foregoing detailed description be regarded asillustrative rather than limiting and that it is understood that thefollowing claims including all equivalents are intended to define thescope of the invention. The claims should not be read as limited to thedescribed order or elements unless stated to that effect. Therefore, allembodiments that come within the scope and spirit of the followingclaims and equivalents thereto are claimed as the invention.

The following example embodiments of the invention are also disclosed:

Embodiment 1

-   -   A method for assigning a number of vehicle lanes on a vehicle        path, the method comprising:    -   receiving, via a processor, location data including a plurality        of location points;    -   projecting, via the processor, the plurality of location points        on to an aggregation axis perpendicular to a centerline of the        vehicle path;    -   grouping, by the processor, the plurality of location points as        projected onto the aggregation axis into one or more clusters;        and    -   determining, by the processor, the number of vehicle lanes of        the vehicle path based on a count of the one or more clusters.

Embodiment 2

The method of embodiment 1, further comprising:

-   -   determining, by the processor, a standard deviation of linear        positions of the plurality of location points as projected onto        the aggregation axis; and    -   removing, by the processor, an outlier subset of location points        of the plurality of location points based on the standard        deviation to define a remainder,    -   wherein the remainder is grouped into the one or more clusters.

Embodiment 3

The method of any of embodiments 1 and 2, further comprising:

-   -   determining, by the processor, a mean of the linear positions of        the plurality of location points as projected onto the        aggregation axis; and    -   determining, by the processor, a linear range on the aggregation        axis based on the mean and the standard deviation,    -   wherein the outlier subset of location points includes location        points located outside of the linear range.

Embodiment 4

The method of any of embodiments 1-3, further comprising:

-   -   fitting, via the processor, one or more linear path segments to        a curvature of the vehicle path; and    -   matching, by the processor, one or more subsets of the location        data to each path segment of the one or more linear path        segments to define the location data for each linear path        segment.

Embodiment 5

The method of any of embodiments 1-4, wherein the number of vehiclelanes of the vehicle path is determined based on a number of lanesdetermined for a majority of the one or more linear path segments of thevehicle path.

Embodiment 6

The method of any of embodiments 1-5, further comprising:

-   -   selecting, by the processor, a representative location point        from a subset of vehicle-common location data points of the        plurality of location data points; and    -   removing, by the processor, the plurality of location points        other than the representative location point from the location        data.

Embodiment 7

The method of any of embodiments 1-6, further comprising:

-   -   determining, by the processor, a centroid of the subset of        vehicle-common location data points,    -   wherein the representative location point is selected based on        the centroid.

Embodiment 8

The method of any of embodiments 1-6, further comprising:

-   -   projecting, by the processor, the subset of vehicle-common        location data points onto a line perpendicular to the centerline        of the vehicle path;    -   determining, by the processor, a mean of the subset of        vehicle-common location data points as projected onto the line,    -   wherein the representative location point is selected based on        the mean.

Embodiment 9

The method of any of embodiments 1-8, further comprising:

-   -   determining, by the processor, a density of the plurality of        location points along the aggregation axis; and    -   removing, by the processor, a subset of location points of the        plurality of location points having a density below a threshold        density.

Embodiment 10

The method of any of embodiments 1-9, wherein grouping the plurality oflocation points into the one or more clusters is repeated for each of aplurality of cluster criteria, and the method further comprises:

-   -   determining, by the processor, a degree of overlap between the        one or more clusters for each grouping according to the        plurality of cluster criteria; and    -   selecting, by the processor, a grouping according to a cluster        criterion of the cluster criteria which resulted in a least        degree of overlap between the one or more clusters.

Embodiment 11

The method of any of embodiments 1-10, further comprising:

-   -   determining, by the processor, a silhouette coefficient for each        location point of the plurality of location points indicating a        similarity between each location point and other location points        in a respective grouping,    -   wherein the grouping is selected for a cluster criterion that        maximizes a total silhouette coefficient of the plurality of        location points.

Embodiment 12

-   -   An apparatus, configured to perform and/or control the method of        any of embodiments 1-11 or comprising means for performing        and/or controlling any of embodiments 1-11.

Embodiment 13

-   -   An apparatus, comprising at least one processor and at least one        memory including computer program code for one or more programs,        the at least one memory and the computer program code configured        to, with the at least one processor, to perform and/or control        the method of any of embodiments 1-11.

Embodiment 14

-   -   A computer program comprising instructions operable to cause a        processor to perform and/or control the method of any of        embodiments 1-11, when the computer program is executed on the        processor.

We claim:
 1. A method for assigning a number of vehicle lanes to avehicle path, the method comprising: receiving, via a processor, aplurality of location points including locations of a plurality ofvehicles; projecting, via the processor, the plurality of locationpoints on to an aggregation axis; grouping, by the processor, theplurality of location points as projected onto the aggregation axis intoone or more clusters; and determining, by the processor, the number ofvehicle lanes based on a count of the one or more clusters.
 2. Themethod of claim 1, further comprising: determining, by the processor, astandard deviation of linear positions of the plurality of locationpoints as projected onto the aggregation axis; and removing, by theprocessor, an outlier subset of location points of the plurality oflocation points based on the standard deviation to define a remainder,wherein the remainder is grouped into the one or more clusters.
 3. Themethod of claim 2, further comprising: determining, by the processor, amean of the linear positions of the plurality of location points asprojected onto the aggregation axis; and determining, by the processor,a linear range on the aggregation axis based on the mean and thestandard deviation, wherein the outlier subset of location pointsincludes location points located outside of the linear range.
 4. Themethod of claim 1, further comprising: fitting, via the processor, oneor more linear path segments to the vehicle path; and matching, by theprocessor, a subset of the plurality of location points to each of theone or more linear path segments.
 5. The method of claim 4, wherein thenumber of vehicle lanes of the vehicle path is determined based on anumber of lanes of a majority of the one or more linear path segments.6. The method of claim 1, further comprising: selecting, by theprocessor, a representative location point from a subset ofvehicle-common location points of the plurality of location points; andremoving, by the processor, the subset of location points other than therepresentative location point from the plurality of location points. 7.The method of claim 6, further comprising: determining, by theprocessor, a centroid of the subset of vehicle-common location points,wherein the representative location point is selected based on thecentroid.
 8. The method of claim 6, further comprising: projecting, bythe processor, the subset of vehicle-common location points onto a lineperpendicular to a centerline of the vehicle path; determining, by theprocessor, a mean of the subset of vehicle-common location points asprojected onto the line, wherein the representative location point isselected based on the mean.
 9. The method of claim 1, furthercomprising: determining, by the processor, a density of the plurality oflocation points along the aggregation axis; and removing, by theprocessor, a subset of location points of the plurality of locationpoints having a density below a threshold density.
 10. The method ofclaim 1, wherein the grouping is performed based on a plurality ofcluster criteria, and wherein the method further comprises: determining,by the processor, a degree of overlap between the one or more clustersfor each grouping performed based the plurality of cluster criteria; andselecting, by the processor, the one or more clusters grouped accordingto a first cluster criterion of the plurality of cluster criteria with aleast degree of overlap between the one or more clusters.
 11. The methodof claim 10, further comprising: determining, by the processor, asilhouette coefficient for the plurality of location points, thesilhouette coefficient indicating a similarity between the plurality oflocation points for each grouping performed based the plurality ofcluster criteria, wherein the one or more clusters is selected based ona second cluster criterion of the plurality of cluster criteria thatmaximizes a total silhouette coefficient of the plurality of locationpoints.
 12. An apparatus for assigning a number of vehicle lanes to avehicle path, the apparatus comprising: a controller comprising a memoryand a processor, the memory storing instructions that, when executed bythe processor, are operable to: receive a plurality of location pointsincluding locations of a plurality of vehicles; project the plurality oflocation points on to an aggregation axis group the plurality oflocation points as projected onto the aggregation axis into one or moreclusters; and determine the number of vehicle lanes of the vehicle pathbased on a count of the one or more clusters.
 13. The apparatus of claim12, wherein the memory stores instructions that, when executed by theprocessor, are further operable to: determine one or more mathematicalquantities based on the plurality of location points; and remove aportion of the plurality of location points.
 14. The apparatus of claim13, wherein the one or more mathematical quantities includes a standarddeviation of linear positions of the plurality of location points asprojected onto the aggregation axis, wherein the portion of theplurality of location points is an outlier subset of the plurality oflocation points based on the standard deviation, and wherein the memorystores instructions that, when executed by the processor, are furtheroperable to group location points of the plurality of location pointsnot included in the outlier subset into the one or more clusters. 15.The apparatus of claim 14, wherein the one or more mathematicalquantities includes a mean of the linear positions of the plurality oflocation points as projected onto the aggregation axis and a linearrange on the aggregation axis based on the mean and the standarddeviation, and wherein the outlier subset includes location pointslocated outside of the linear range.
 16. The apparatus of claim 13,wherein the plurality of location points are recorded by a vehicle ofthe plurality of vehicles, wherein the one or more mathematicalquantities includes a centroid of the plurality of location pointsrecorded by the vehicle, and wherein the portion of the plurality oflocation points includes a plurality of location points recorded by thevehicle other than a representative location point, the representativelocation point being based on the centroid.
 17. The apparatus of claim13, wherein the one or more mathematical quantities includes a densityof the plurality of location points along the aggregation axis, andwherein the portion of the plurality of location points includes asubset of location points of the plurality of location points having adensity below a threshold density.
 18. The apparatus of claim 13,wherein the memory stores instructions that, when executed by theprocessor, are further operable to: repeat grouping the plurality oflocation points as projected onto the aggregation axis into one or moreclusters for each of a plurality of cluster criteria, wherein the one ormore mathematical quantities includes a degree of overlap between theone or more clusters for each grouping according to the plurality ofcriteria; and select a grouping according to a cluster criterion of thecluster criteria which resulted in a least degree of overlap between theone or more clusters.
 19. The apparatus of claim 12, wherein the memorystores instructions that, when executed by the processor, are furtheroperable to: fit one or more linear path segments to the vehicle pathand match one or more subsets of the plurality of location points toeach linear path segment of the one or more linear path segments;project the plurality of location points and group location points ofthe plurality of location points into the one or more clusters for eachlinear path segment of the one or more linear path segments and for theone or more subsets matched to each respective path segment; anddetermine a number of vehicle lanes for each linear path segment of theone or more linear path segments based on the count of the one or moreclusters associated with each linear path segment.
 20. A non-transitorycomputer-readable medium including instructions that when executed areoperable to: receive a plurality of location points representing aplurality of mobile devices traversing a path in a travel direction;project the plurality of location points on to an aggregation axis ofthe path; group the plurality of location points travel into one or moreclusters based on the location points as projected onto the aggregationaxis; and determine a number of traffic lanes and a direction of thepath based on a count of the one or more clusters and the traveldirection.